Control method and local control plane device

ABSTRACT

Embodiments of the present disclosure disclose a control method, the method is applied to a wireless communications system, and the wireless communications system includes user equipment, a base station, a gateway device, a local control plane device, and a remote control plane device. The method includes: obtaining, by the local control plane device, context information of the user equipment from the remote control plane device according to an interaction process between the user equipment and the remote control plane device; and setting up, by the local control plane device according to the context information of the user equipment, a radio bearer between the user equipment and a base station in which a current camping cell of the user equipment is located.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/908,225, filed on Feb. 28, 2018, which is a continuation ofInternational Application No. PCT/CN2015/090270, filed on Sep. 22, 2015.All of the aforementioned patent applications are hereby incorporated byreference in their entireties.

TECHNICAL FIELD

The present disclosure relates to the field of wireless communicationstechnologies, and in particular, to a control method and a local controlplane device.

BACKGROUND

Currently, 3GPP (3rd Generation Partnership Project) proposes abrand-new EPS (evolved packet system) network including UE (userequipment), an eNB (Evolutional Node B, E-UTRAN Node B), an SGW (ServingGateway), a PGW (packet data network gateway), and an MME (mobilitymanagement entity). The SGW serves as a forwarding plane anchor betweenaccess networks, and the PGW serves as a forwarding plane anchor betweenan access network and a non-access network. To ensure continuity of IPaddresses of the UE, the PGW is deployed at a relatively high position.In this way, even if the UE moves, the UE always keeps connection to thePGW, thereby ensuring that an IP address remains unchanged. However, ifthe UE accesses a local server, a route recurvation problem occurs, thatis, data of the UE first arrives at the PGW at a relatively highposition, and then returns to the local server. Consequently, a packettransmission delay gets longer.

To resolve this problem, 3GPP defines an SIPTO (Selected IP TrafficOffload) function. A core idea of the SIPTO function is to deploy theSGW and the PGW at low positions. When the UE accesses the local server,a local PGW allocates an IP address, and data passes through only alocal SGW and the local PGW, thereby avoiding route recurvation, andresolving a problem of an extremely long packet transmission delay.However, a disadvantage of deploying the SGW and the PGW at lowpositions is that the SGW and the PGW are relatively far away from acentrally deployed MME, and consequently a signaling transmission delaygets longer when the UE switches from an idle state to an active state.Therefore, another method for reducing the signaling transmission delayis to shift the MME downwards to a low position and deploy the MME andthe local gateway together. However, this greatly reduces a quantity ofUEs managed by each MME. When UE moves, the UE tends to switch betweendifferent MMEs, and consequently signaling interaction increases, andsystem load increases.

SUMMARY

Embodiments of the present disclosure provide a control method and alocal control plane device, to reduce a signaling transmission delaycaused when user equipment switches from an idle state to an activestate, and to avoid a problem of excessive signaling interaction causedby frequent control plane switching due to a movement of the userequipment.

A first aspect of an embodiment of the present disclosure provides acontrol method, where the method is applied to a wireless communicationssystem, the wireless communications system includes user equipment, abase station, a gateway device, a local control plane device, and aremote control plane device, and the method includes:

obtaining, by the local control plane device, context information of theuser equipment from the remote control plane device according to aninteraction process between the user equipment and the remote controlplane device; and

setting up, by the local control plane device according to the contextinformation of the user equipment, a radio bearer between the userequipment and a base station in which a current camping cell of the userequipment is located.

A second aspect of an embodiment of the present disclosure provides alocal control plane device, the local control plane device is applied toa wireless communications system, the wireless communications systemfurther includes user equipment, a base station, a gateway device, and aremote control plane device, and the local control plane deviceincludes:

an information obtaining module, configured to obtain contextinformation of the user equipment from the remote control plane deviceaccording to an interaction process between the user equipment and theremote control plane device; and

a bearer setup module, configured to set up, by the local control planedevice according to the context information of the user equipment, aradio bearer between the user equipment and a base station in which acurrent camping cell of the user equipment is located.

It can be learned from the foregoing that, in the embodiments of thepresent disclosure, the local control plane device obtains the contextinformation of the user equipment from the remote control plane deviceaccording to the interaction process between the user equipment and theremote control plane device, and further sets up, according to thecontext information of the user equipment, the radio bearer between theuser equipment and the base station in which the current camping cell ofthe user equipment is located. Therefore, a signaling transmission delaycaused when the user equipment switches from an idle state to an activestate can be reduced, and a problem of excessive signaling interactioncaused by frequent control plane switching due to a movement of the userequipment can be avoided.

BRIEF DESCRIPTION OF DRAWINGS

To describe embodiments of the present disclosure more clearly, thefollowing briefly describes the accompanying drawings required fordescribing the embodiments.

FIG. 1 is a schematic flowchart of a control method according to anembodiment of the present disclosure;

FIG. 2A, FIG. 2B, and FIG. 2C are a schematic flowchart of a controlmethod according to a first embodiment of the present disclosure;

FIG. 3A, FIG. 3B, FIG. 3C, and FIG. 3D are a schematic flowchart ofanother control method according to a first embodiment of the presentdisclosure;

FIG. 4A, FIG. 4B, and FIG. 4C are a schematic flowchart of a controlmethod according to a second embodiment of the present disclosure;

FIG. 5A, FIG. 5B, and FIG. 5C are a schematic flowchart of anothercontrol method according to a second embodiment of the presentdisclosure;

FIG. 6 is a schematic structural diagram of a local control plane deviceaccording to an embodiment of the present disclosure;

FIG. 7 is a schematic structural diagram of an information obtainingmodule according to an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of another informationobtaining module according to an embodiment of the present disclosure;

FIG. 9 is a schematic structural diagram of another local control planedevice according to an embodiment of the present disclosure;

FIG. 10 is a schematic diagram of an architecture of a wirelesscommunications system according to a first embodiment of the presentdisclosure; and

FIG. 11 is a schematic diagram of an architecture of a wirelesscommunications system according to a second embodiment of the presentdisclosure.

DESCRIPTION OF EMBODIMENTS

The following clearly describes the technical solutions in theembodiments of the present disclosure with reference to the accompanyingdrawings in the embodiments of the present disclosure.

The technical solutions of the embodiments of the present disclosure maybe applied to various communications systems, such as: a Global Systemof Mobile Communications (GSM) system, a Code Division Multiple Access(CDMA) system, a Wideband Code Division Multiple Access (WCDMA) system,a general packet radio service (GPRS), a Long Term Evolution (LTE)system, an LTE frequency division duplex (FDD) system, an LTE timedivision duplex (TDD), a Universal Mobile Telecommunications System(UMTS), or a Worldwide Interoperability for Microwave Access (WiMAX)communications system.

In the embodiments of the present disclosure, user equipment (UE) mayinclude a terminal, a mobile station (MS), a mobile terminal, and thelike. The user equipment may communicate with one or more core networksthrough a radio access network (RAN). For example, the user equipmentmay be a mobile phone (also referred to as a “cellular” phone) or acomputer with a mobile terminal. For example, the user equipment mayalso be a portable, pocket-sized, handheld, computer built-in, orin-vehicle mobile apparatus, which exchanges voice and/or data with theradio access network. In the embodiments of the present disclosure, abase station may be an E-UTRAN NodeB (Evolutional Node B, “eNB”) in LTE.

FIG. 1 is a schematic flowchart of a control method according to anembodiment of the present disclosure. The method is applied to awireless communications system, and the wireless communications systemincludes user equipment, a base station, a gateway device, a localcontrol plane device, and a remote control plane device. As shown in thefigure, a process of the control method in this embodiment may includethe following operations.

S101. The local control plane device obtains context information of theuser equipment from the remote control plane device according to aninteraction process between the user equipment and the remote controlplane device.

The context information of the user equipment includes at least asecurity context and a bearer context (including a user-plane addressand a user-plane TEID-U of an SGW, a TAI (tracking area identity) list,a GUTI (globally unique temporary identity), a control-plane TEID-Callocated by an MME, and a TEID-C allocated by the SGW). The TEID(Tunnel Endpoint ID) is a tunnel endpoint identifier.

In one embodiment, the interaction process between the user equipmentand the remote control plane device includes an attach request processand a packet data network (PDN) connection setup process that areinitiated by the user equipment.

In one embodiment, the local control plane device obtains the contextinformation of the user equipment from the remote control plane deviceaccording to the interaction process between the user equipment and theremote control plane device in the following two manners:

Manner 1: In the interaction process between the user equipment and theremote control plane device, the local control plane device forwards, tothe gateway device, forwarding plane modification information sent bythe remote control plane device, where the forwarding plane modificationinformation carries the context information of the user equipment.Further, the local control plane device may obtain the contextinformation of the user equipment by parsing the forwarding planemodification information.

It should be noted that the forwarding plane modification informationherein may be a bearer modification request in an application scenariodescribed in FIG. 2A, FIG. 2B, and FIG. 2C in the following. That is,when forwarding, to the gateway device, a bearer modification requestsent by the remote control plane device, the local control plane deviceparses the context information of the user equipment carried in thebearer modification request. Alternatively, the forwarding planemodification information herein may be a downlink data forwarding rulemodification message in an application scenario described in FIG. 4A,FIG. 4B, and FIG. 4C in the following. That is, when forwarding, to thegateway device, a downlink data forwarding rule modification messagesent by the remote control plane device, the local control plane deviceparses the context information of the user equipment carried in thedownlink data forwarding rule modification message.

Manner 2: In the interaction process between the user equipment and theremote control plane device, the local control plane device forwards, tothe gateway device, forwarding plane modification information sent bythe remote control plane device, and receives the context information ofthe user equipment directly sent by the remote control plane device.

S102. The local control plane device sets up, according to the contextinformation of the user equipment, a radio bearer between the userequipment and a base station in which a current camping cell of the userequipment is located.

In one embodiment, after receiving a service request sent by the userequipment via the base station in which the current camping cell of theuser equipment is located, the local control plane device sends acontext setup request to the base station according to the contextinformation of the user equipment, so that the base station sets up theradio bearer between the base station and the user equipment.

It should be noted that sending the service request by the userequipment via the base station in which the current camping cell of theuser equipment is located may be triggered by a downlink data arrivalnotification. In one embodiment, when the user equipment is in an idlestate, the local control plane device initiates paging to the userequipment according to the context information of the user equipmentafter receiving a downlink data arrival notification message, so thatthe user equipment switches from the idle state to an active state, andsends the service request via the base station in which the currentcamping cell is located.

In addition, when the user equipment performs a cross-domain movement toa new tracking area range, a base station to which the user equipmentbelongs changes, and a local control plane device and a gateway devicechange. Therefore, the source local control plane device and the sourcegateway device delete the stored context information of the userequipment. In one embodiment, after receiving a context deletion requestsent by the remote control plane device, the source local control planedevice deletes the stored context information of the user equipment andsends the context deletion request to the source gateway device, so thatthe source gateway device deletes the stored context information of theuser equipment. It should be noted that the source gateway device hereinincludes a source SGW but does not include a source PGW.

Further, after the local control plane device sets up the radio bearerbetween the base station and the user equipment, the local control planedevice processes paging and service request processes of the userequipment. When the user equipment switches from an idle state to anactive state, the local control plane device sends a user statemodification notification to the remote control plane device, so thatthe remote control plane device modifies state information of the userequipment.

It can be learned from the foregoing that, in this embodiment of thepresent disclosure, the local control plane device is introduced into anexisting wireless network system and has the following functions: asignaling proxy between the base station and the remote control planedevice and a signaling proxy between the remote control plane device andthe local gateway device. The local control plane device may store abearer context and a security context of a user, and a user TAI list,and is responsible for the paging and service request processes of theuser. Other processes are still processed by the remote control planedevice in the existing wireless network system. In this embodiment ofthe present disclosure, some functions of the remote control planedevice in the existing wireless network system are deployed in adistributed manner, so that paging and service request functions can belocally implemented. Therefore, a time required for signalingtransmission is reduced, a shorter time required for switching from anidle state to an active state is provided for an ultra-low delayapplication, and an initial packet transmission delay is reduced.

FIG. 2A, FIG. 2B, and FIG. 2C are a schematic flowchart of a controlmethod according to a first embodiment of the present disclosure. Themethod is applied to a wireless communications system, and the wirelesscommunications system includes user equipment, a base station, a gatewaydevice, a local control plane device, and a remote control plane device.

FIG. 10 is a schematic diagram of an architecture of the wirelesscommunications system according to the first embodiment of the presentdisclosure. As shown in the figure, on the basis of a centralizedgateway deployment scenario of SIPTO (Selected IP Traffic Offload) of amacro network, a new function entity: the local control plane device(Local Control, LC), is introduced into the architecture. The localcontrol plane device integrates an offloading function with an SGW and aPGW, and is close to an access network. In the figure, an S1 interfaceis an interface between a remote control plane and the base station, andan S11 interface is an interface between the remote control plane andthe SGW. A local control plane is a signaling proxy between the twointerfaces, serves as an MME for the base station and the SGW, andserves as a base station and an SGW for the remote control plane. Thegateway device includes the SGW/PGW, and the remote control plane deviceincludes an MME in a conventional network architecture.

As shown in FIG. 2A, FIG. 2B, and FIG. 2C, a process of the controlmethod in this embodiment may include the following operations.

S201. The user equipment sends an attach request to the base station.

In one embodiment, the UE sends the attach request to an eNB to initiatea network attach process. The attach request carries an IMSI(international mobile subscriber identity), a core network capability, aPDN type, and a selected PLMN (public land mobile network) of the UE.

S202. The base station sends the attach request to the local controlplane device.

In one embodiment, the eNB sends an S1AP initial UE message to the localcontrol plane device, and the S1AP initial UE message carries the attachrequest.

S203. The local control plane device sends the attach request to theremote control plane device.

In one embodiment, the local control plane device sends the attachrequest to the MME.

S204. The local control plane device performs authentication on the userequipment and a security setup process.

In one embodiment, if there is no context information of the UE in anetwork, the MME performs authentication on the UE and a NAS (networkattached storage) security setup process. Subsequently, all NAS messagesare protected by a NAS security function indicated by the MME.

S205. The remote control plane device sends a session setup request tothe local control plane device.

In one embodiment, the MME sends the session setup request to the localcontrol plane device. The session setup request includes informationsuch as an EPS bearer identity, an APN (access point name) of the UE, acontrol-plane MME TEID, default EPS bearer QoS (Quality of Service), anda PDN type.

S206. The local control plane device sends the session setup request tothe gateway device.

In one embodiment, the local control plane device forwards the sessionsetup request to the SGW/PGW.

S207. The gateway device sends a session setup response to the localcontrol plane device.

In one embodiment, the SGW/PGW returns the session setup response. Thesession setup response includes information such as the PDN type, an SGWuser-plane address and TEID, an SGW control-plane TEID, the EPS beareridentity, EPS bearer QoS, and a PGW address and TEID.

S208. The local control plane device sends the session setup response tothe remote control plane device.

In one embodiment, the local control plane device forwards the sessionsetup response to the MME.

S209. The remote control plane device sends an initial context setuprequest to the base station by using the local control plane device.

In one embodiment, the MME sends the S1AP initial context setup requestto the eNB. The S1AP initial context setup request carries an attachaccept message. In addition, the S1AP message includes information suchas a security context of the UE, the EPS bearer QoS, the EPS beareridentity, and the SGW user-plane address and TEID. The attach acceptmessage includes information such as a GUTI, the PDN type, a PDNaddress, an APN, and a TAI list.

S210. The base station performs radio resource control connectionconfiguration with the user equipment.

In one embodiment, a process of the RRC (radio resource control)connection configuration is completed between the eNB and the UE.

S211. The base station sends an initial context setup response to theremote control plane device by using the local control plane device.

In one embodiment, the eNB returns an initial context setup responsemessage. The initial context setup response message includes an addressand a TEID of an eNB that transmits downlink data on an S1-U interface,and an attach complete message of the UE.

S212. The remote control plane device sends a bearer modificationrequest to the local control plane device.

In one embodiment, the MME sends the bearer modification request to thelocal control plane device. The bearer modification request includes theEPS bearer identity, and the address and TEID of the eNB.

S213. The local control plane device obtains context information of theuser equipment.

In one embodiment, the local control plane device obtains the contextinformation of the UE from the MME in the following two manners:

Manner 1: The bearer modification request sent by the MME carries thecontext information of the UE. The local control plane device may obtainthe context information of the UE by parsing the bearer modificationrequest.

Manner 2: The local control plane device receives the contextinformation of the UE that is directly sent by the MME.

The context information of the UE includes the security context, thebearer context (which already includes a user-plane address, auser-plane TEID-U of the SGW, the TAI list, the GUTI, a control-planeTEID-C allocated by the MME, and a TEID-C allocated by the SGW herein).The local control plane device stores this information.

S214. The local control plane device sends the bearer modificationrequest to the gateway device.

In one embodiment, the local control plane device forwards the bearermodification request to the SGW/PGW.

S215. The gateway device sends a bearer modification response to thelocal control plane device.

In one embodiment, the SGW/PGW returns the bearer modification response.The bearer modification response carries the EPS bearer identity.

S216. The local control plane device sends the bearer modificationresponse to the remote control plane device.

In one embodiment, the local control plane device notifies the MME of abearer modification response message.

S217. After receiving a downlink data arrival notification message, thelocal control plane device initiates paging to the user equipment.

In one embodiment, after the UE enters an idle state and has thedownlink data arrival notification message, the local control planedevice determines stored context information according to the TEID-Callocated by the MME, obtains the TAI list, and sends paging messages toall eNBs in the TAI list to which the UE belongs, where the pagingmessage carries an S-TMSI (some information of the GUTI). The eNBinitiates paging to the UE.

S218. The user equipment sends a service request to the local controlplane device via the base station.

In one embodiment, the UE responds to the paging message, enters anactive state again, and sends the service request to the local controlplane device. The service request carries the S-TMSI.

S219. The local control plane device sends a context setup request tothe base station.

In one embodiment, the local control plane device finds, according tothe S-TMSI, a bearer context (including the EPS bearer QoS, the EPSbearer identity, the SGW user-plane address, and the SGW user-planeTEID-U) and a security context that are correspondingly stored, sends aninitial context setup request message to the eNB, sets up a transmissiontunnel between the eNB and the SGW/PGW according to the stored bearercontext, and sends the security context to the eNB to ensure securetransmission between the UE and the eNB.

S220. The base station sends a context setup complete message to thelocal control plane device.

In one embodiment, after completing a user-plane radio bearer setupprocess, the eNB returns an initial context setup complete message tothe local control plane device. The initial context setup completemessage carries an address and a TEID of an eNB that are used totransmit downlink data on the S1 interface, an EPS bearer list acceptedby the eNB, and in one embodiment, a rejected EPS bearer list.

Further, the local control plane device sends the bearer modificationrequest to the SGW/PGW. The bearer modification request carries theTEID-C allocated by the SGW, the EPS bearer list (the address anduser-plane TEID of the eNB that transmits downlink data on the S1interface) accepted by the eNB, and in one embodiment, the EPS bearerlist rejected by the eNB.

S221. The local control plane device sends a user state modificationnotification to the remote control plane device.

In one embodiment, because the UE switches from an idle state to anactive state, the local control plane device notifies the MME of alatest state of the UE. A purpose of this is to avoid repeatedly pagingto the UE when the MME needs to convey signaling to the UE. In addition,in the foregoing process, if there is a rejected EPS bearer, the MMEneeds to delete the EPS bearer rejected on a core network.

FIG. 3A, FIG. 3B, FIG. 3C, and FIG. 3D are a schematic flowchart ofanother control method according to a first embodiment of the presentdisclosure. As shown in the figure, a process of the control method inthis embodiment may include the following operations.

S301. User equipment sends a tracking area update request to a remotecontrol plane device.

It should be noted that when the UE performs a cross-domain movement toa new tracking area, the UE sends the TA (tracking area) update requestto an MME to trigger a TA update process.

S302. The remote control plane device sends a session setup request to atarget local control plane device.

In one embodiment, the MME stores context information of the UE andsends the session setup request to the target local control planedevice. The session setup request carries an MME address, acontrol-plane TEID, and a bearer context (including an address of asource PGW1).

S303. The target local control plane device sends the session setuprequest to a target gateway device.

In one embodiment, the target local control plane device transmits thesession setup request to an SGW2.

Further, the SGW2 sends a bearer modification request according to theaddress of the PGW1 and sets up an S5 connection from the SGW2 to thePGW1.

S304. The remote control plane device sends a session deletion requestto a source local control plane device.

In one embodiment, the MME sends the session deletion request to thesource local control plane device. The session deletion request carriesa TEID-C allocated by the MME.

S305. The source local control plane device deletes context informationof the user equipment.

In one embodiment, the source local control plane device deletes thecorresponding context information according to the TEID-C allocated bythe MME.

S306. The source local control plane device sends the session deletionrequest to a source gateway device.

In one embodiment, the source local control plane device sends thesession deletion request to an SGW1.

S307. The source gateway device deletes context information of the userequipment.

In one embodiment, the SGW1 deletes the corresponding contextinformation.

S308. The remote control plane device sends an initial context setuprequest to a base station by using the target local control planedevice.

In one embodiment, the MME sends the initial context (including an SGWuser-plane address and TEID-U) setup request to the base station byusing the target local control plane device. The initial context setuprequest includes a TA update accept message (a GUTI, a TAI list, and anEPS bearer status).

S309. The base station performs radio resource control connectionconfiguration with the user equipment.

In one embodiment, after receiving the initial context setup request,the eNB performs RRC connection reconfiguration to set up a radio bearerbetween the eNB and the UE. In addition, the UE deletes a local resourceof a bearer that is not marked as “active” in the received EPS bearerstatus, and returns an RRC connection reconfiguration complete message.

S310. The base station sends an initial context setup response to theremote control plane device.

In one embodiment, the eNB sends the initial context setup response tothe MME to return an address and a TEID of an eNB that transmitsdownlink data on an S1 interface.

S311. The remote control plane device sends a bearer modificationrequest to the target local control plane device.

In one embodiment, the MME sends the bearer modification request to thetarget local control plane device. The bearer modification requestincludes an EPS bearer identity, and the address and TEID of the eNB.

S312. The target local control plane device forwards the bearermodification request to the source gateway device.

S313. The source gateway device sends a bearer modification response tothe target local control plane device.

In one embodiment, the SGW1/PGW1 sends the bearer modification responseto the target local control plane device. The bearer modificationresponse includes the EPS bearer identity. Then, the target localcontrol plane device notifies the MME of the bearer modificationresponse, so that the MME instructs the UE to release a PDN connectionbetween the SGW2 and the PGW1 and delete all bearer contexts in a PDNconnection process, and instructs the UE to initiate a PDN connectionre-setup process and set up a PDN connection between the local SGW2 anda PGW2.

S314. The user equipment sends a network connection request to theremote control plane device via the base station.

In one embodiment, the UE sends a PDN connection request to the MME viathe eNB.

S315. The remote control plane device sends a session setup request tothe target local control plane device.

In one embodiment, the MME sends the session setup request to the targetlocal control plane device. The session setup request includesinformation such as an address of the target PGW2, the EPS beareridentity, an APN of a user, a control-plane MME TEID-C, default EPSbearer QoS, and a PDN type.

S316. The target local control plane device sends the session setuprequest to the target gateway device.

In one embodiment, the target local control plane device transmits asession setup request message to the SGW2.

S317. The target gateway device sends a session setup response to thetarget local control plane device.

In one embodiment, the SGW2 sends the bearer modification requestaccording to the address of the PGW2, sets up an S5 connection from theSGW2 to the PGW2, and then returns the session setup response to thetarget local control plane device. In addition, the returned sessionsetup response includes information such as a PDN type, an S-GWuser-plane address and TEID, an S-GW control-plane TEID, an EPS beareridentity, EPS bearer QoS, and a P-GW address and TEID.

S318. The remote control plane device sends a bearer setup request tothe base station.

In one embodiment, the MME sends the bearer setup request to the UE viathe eNB. The bearer setup request carries a PDN connection acceptmessage (an APN, the PDN type, a PDN address, and the EPS beareridentity) and includes the EPS bearer QoS and the S-GW user-planeaddress and TEID.

S319. The base station performs radio resource control connectionconfiguration with the user equipment.

In one embodiment, RRC connection reconfiguration is completed betweenthe eNB and the UE.

S320. The base station sends a bearer setup complete message to theremote control plane device.

In one embodiment, the eNB returns the bearer setup complete message tothe MME. The bearer setup complete message includes an address and aTEID of an eNB that transmits downlink data on S1-U. Then, the UE sendsa direct transmission message including a PDN connection completemessage to the eNB.

Further, the eNB sends the bearer setup complete message to the MME. Thebearer setup complete message carries the PDN connection completemessage.

S321. The remote control plane device sends a bearer modificationrequest to the target local control plane device.

In one embodiment, the MME sends the bearer modification request to thetarget local control plane device. The bearer modification requestincludes the EPS bearer identity, and the address and TEID of the eNB.

S322. The target local control plane device obtains the contextinformation of the user equipment.

In one embodiment, the target local control plane device obtains thecontext information of the UE in the following two manners:

Manner 1: The bearer modification request sent by the MME carries thecontext information of the UE. The target local control plane device mayobtain the context information of the UE by parsing the bearermodification request.

Manner 2: The target local control plane device receives the contextinformation of the UE that is directly sent by the MME.

The context information of the UE includes the security context, thebearer context (which already includes a user-plane address, auser-plane TEID-U of the SGW, the TAI list, the GUTI, a control-planeTEID-C allocated by the MME, and a TEID-C allocated by the SGW herein).The local control plane device stores this information.

Further, the target local control plane device forwards the bearermodification request to the SGW2/PGW2, and further the SGW2/PGW2 returnsthe bearer modification response including the EPS bearer identity.

It can be learned from the foregoing that, in this embodiment of thepresent disclosure, the local control plane is responsible for pagingand service request processes and has S1 signaling and S11 signalingproxy functions. A signaling transmission path and time are greatlyshortened, signaling interaction caused by frequent switching betweenMMEs in the prior art is avoided, and frequently updating user locationinformation by an HSS caused by mobility of the UE is also avoided.

FIG. 4A, FIG. 4B, and FIG. 4C are a schematic flowchart of a controlmethod according to a second embodiment of the present disclosure. Themethod is applied to a wireless communications system, and the wirelesscommunications system includes user equipment, a base station, a gatewaydevice, a local control plane device, and a remote control plane device.

FIG. 11 is a schematic diagram of an architecture of the wirelesscommunications system according to the second embodiment of the presentdisclosure. As shown in the figure, on the basis of a mobile networkarchitecture in which forwarding is separated, a local control planedevice is introduced into the architecture. A control plane function(GW-C) and a forwarding plane function (GW-U) of a gateway device aredecoupled. A control plane function obtained by decoupling, and an MME,a PCRF (policy and charging rules function), and the like in aconventional network architecture are combined into a remote controlplane device that is alternatively referred to as a central controlplane device (Central Control, CC). A forwarding plane function (SGW-U)of an SGW and a forwarding plane function (PGW-U) of a PGW are combinedinto a gateway device (GW-U), and a mobile flow interface is a referencepoint used after data forwarding of the gateway is separated.

As shown in FIG. 4A, FIG. 4B, and FIG. 4C, a process of the controlmethod in this embodiment may include the following operations.

S401. The user equipment sends an attach request to the base station.

In one embodiment, the UE sends the attach request to an eNB.

S402. The base station sends the attach request to the local controlplane device.

In one embodiment, the eNB sends the attach request to the local controlplane device.

S403. The local control plane device sends the attach request to theremote control plane device.

In one embodiment, the local control plane device forwards the attachrequest to the remote control plane device, so that authentication iscompleted between the remote control plane device and the UE.

S404. The remote control plane device sends an uplink data forwardingrule to the local control plane device.

In one embodiment, the remote control plane device allocates an uplinktunnel identifier, and delivers the uplink data forwarding rule. Theuplink data forwarding rule includes index information.

S405. The local control plane device sends the uplink data forwardingrule to the gateway device.

In one embodiment, the local control plane device sends the uplink dataforwarding rule to the GW-U, so that the GW-U performs forwardingaccording to the uplink data forwarding rule.

S406. The remote control plane device sends an initial context setuprequest to the base station by using the local control plane device.

In one embodiment, the remote control plane device sends the initialcontext setup request to the eNB. The initial context setup requestincludes the allocated uplink tunnel identifier.

S407. The base station performs radio resource control connectionconfiguration with the user equipment.

In one embodiment, RRC connection configuration is completed between theeNB and the UE.

S408. The base station sends an initial context setup response to theremote control plane device by using the local control plane device.

In one embodiment, the eNB returns the initial context setup response toa control plane. The initial context setup response includes a downlinktunnel ID allocated by the eNB and an attach complete message.

S409. The remote control plane device sends a downlink data forwardingrule to the local control plane device.

The downlink data forwarding rule includes index information thatindicates a manner in which the GW-U sends an IP packet to the UE.

S410. The local control plane device obtains context information of theuser equipment.

In one embodiment, the local control plane device obtains the contextinformation of the UE in the following two manners:

Manner 1: A downlink data forwarding rule modification message sent bythe remote control plane device carries the context information of theUE. The local control plane device may obtain the context information ofthe UE by parsing the downlink data forwarding rule modificationmessage.

Manner 2: The local control plane device receives the contextinformation of the UE that is directly sent by the remote control planedevice.

The context information of the UE includes a UE security context, abearer context, a TAI list, a GUTI, and index information of uplink anddownlink data forwarding rules. The local control plane device storesthis information.

S411. The local control plane device sends a downlink data forwardingrule modification message to the gateway device.

In one embodiment, the local control plane device notifies the GW-U ofthe downlink data forwarding rule.

S412. After receiving a downlink data arrival notification message, thelocal control plane device initiates paging to the user equipment.

In one embodiment, when the user equipment enters an idle state, theGW-U matches the downlink data forwarding rule, buffers downlink data,and sends the downlink data arrival notification message to the localcontrol plane device. The downlink data arrival notification messageincludes index information corresponding to the downlink data forwardingrule. The local control plane device determines a corresponding TAI listof the UE according to the index information of the downlink dataforwarding rule, and sends paging messages to all eNBs in the TAI listto which the UE belongs. The message carries an S-TMSI (some informationof the GUTI), so that the eNB initiates paging to the UE.

S413. The user equipment sends a service request to the local controlplane device via the base station.

In one embodiment, the UE responds to the paging message, enters anactive state again, and sends the service request to the local controlplane device. The service request carries the S-TMSI (some informationof the GUTI).

S414. The local control plane device sends a context setup request tothe base station.

In one embodiment, the local control plane device finds, according tothe S-TMSI, a bearer context (including EPS bearer QoS, an EPS beareridentity, and the uplink tunnel identifier) and a security context thatare correspondingly stored, and sends the initial context setup requestto the eNB, so that the eNB sets up a transmission tunnel between theeNB and the GW-U according to the stored bearer context, and sends thesecurity context to the eNB to ensure secure transmission between the UEand the eNB.

S415. The base station sends a context setup complete message to thelocal control plane device.

In one embodiment, after completing a user-plane radio bearer setupprocess, the eNB returns the initial context setup complete message. Theinitial context setup complete message includes a tunnel identifier ofan eNB that transmits downlink data.

S416. The local control plane device sends a downlink data forwardingrule modification message to the remote control plane device.

In one embodiment, after obtaining the tunnel identifier of the eNB, thelocal control plane device updates the downlink data forwarding rule ofthe UE according to a buffered downlink data forwarding rule index, andsets up a transmission tunnel between the eNB and the GW-U, so that theGW-U sends a buffered packet to the eNB.

S417. The local control plane device sends a user state modificationnotification to the remote control plane device.

In one embodiment, because the UE switches from an idle state to anactive state, the local control plane device notifies the remote controlplane device of a latest state of the UE.

FIG. 5A, FIG. 5B, and FIG. 5C are a schematic flowchart of anothercontrol method according to a second embodiment of the presentdisclosure. As shown in the figure, a process of the control method inthis embodiment may include the following operations.

S501. User equipment sends a tracking area update request to a remotecontrol plane device.

It should be noted that when the UE performs a cross-domain movement toa new tracking area range, the UE sends the TA update request to theremote control plane device to trigger a TA update process.

S502. The remote control plane device sends an uplink data forwardingrule to a target local control plane device.

In one embodiment, the remote control plane device allocates an uplinktunnel identifier, and delivers the uplink data forwarding rule to thetarget local control plane device. The uplink data forwarding ruleincludes index information.

S503. The target local control plane device sends the uplink dataforwarding rule to a target gateway device.

In one embodiment, the target local control plane device instructs aGW-U2 to accept a packet of a tunnel and perform forwarding according tothe uplink data forwarding rule.

S504. The remote control plane device sends a context release command toa source local control plane device.

S505. The source local control plane device deletes context informationof the user equipment.

In one embodiment, the source local control plane device deletes thecorresponding context information of the UE according to the contextrelease command.

S506. The source local control plane device sends the context releasecommand to a source gateway device.

In one embodiment, the source local control plane device sends thecontext release command to a GW-U1.

S507. The source gateway device deletes context information of the userequipment.

In one embodiment, the GW-U1 deletes the corresponding contextinformation of the UE according to the context release command.

S508. The remote control plane device sends an initial context setuprequest to a base station by using the target local control planedevice.

In one embodiment, the remote control plane device sends the initialcontext setup request to the base station. The initial context setuprequest includes the allocated uplink tunnel identifier, and carries aTAU accept message. The TAU accept message includes information such asa GUTI, a PDN type, a PDN address, an APN, and a TAI list.

S509. The base station performs radio resource control connectionconfiguration with the user equipment.

S510. The base station sends an initial context setup response to theremote control plane device.

In one embodiment, the eNB returns the initial context setup response tothe remote control plane device. The initial context setup responseincludes a downlink tunnel ID allocated by the eNB.

S511. The remote control plane device sends a downlink data forwardingrule modification message to the target local control plane device.

In one embodiment, the remote control plane device sends the downlinkdata forwarding rule modification message to the target local controlplane device. The downlink data forwarding rule modification messageincludes index information that indicates a manner in which the GW-Usends an IP packet to the UE.

S512. The target local control plane device forwards the downlink dataforwarding rule modification message to the target gateway device.

In one embodiment, the target local control plane device notifies theGW-U2 of the downlink data forwarding rule modification message.

S513. The user equipment sends a network connection request to theremote control plane device via the base station.

In one embodiment, the remote control plane device instructs the UE toperform PDN connection release and delete all bearers in a source PDNconnection process, and instructs the UE to initiate PDN connectionre-setup. In this process, the UE sends the network connection requestto the remote control plane device via the eNB.

S514. The remote control plane device sends a downlink data forwardingrule to the target local control plane device.

In one embodiment, the remote control plane device allocates the uplinktunnel identifier, and delivers the downlink data forwarding rule. Thedownlink data forwarding rule includes index information that indicatesa manner in which the GW-U sends an IP packet to the UE.

S515. The target local control plane device sends the downlink dataforwarding rule to the target gateway device.

In one embodiment, the target local control plane device instructs theGW-U2 to accept a packet of a tunnel and perform forwarding according tothe downlink data forwarding rule.

S516. The remote control plane device sends a bearer setup request tothe base station.

In one embodiment, the remote control plane device sends the bearersetup request to the eNB. The bearer setup request carries a PDNconnection accept message (the APN, the PDN type, the PDN address, andthe EPS bearer identity), and the PDN connection accept message includesthe allocated uplink tunnel identifier.

S517. The base station performs radio resource control connectionconfiguration with the user equipment.

S518. The base station sends a bearer setup complete message to theremote control plane device.

It should be noted that, before that, the eNB returns a bearer setupresponse to the remote control plane device. The bearer setup responseincludes an address and a TEID of an eNB that transmits downlink data onan S1-U interface. Then, the UE sends a direct transmission message tothe eNB, and the direct transmission message includes a PDN connectioncomplete message.

In one embodiment, the eNB transmits the PDN connection complete messageto the remote control plane device.

S519. The remote control plane device sends a downlink data forwardingrule modification message to the local control plane device.

The downlink data forwarding rule modification message includes indexinformation that indicates a manner in which the GW-U sends an IP packetto the UE.

S520. The target local control plane device obtains the contextinformation of the user equipment.

In one embodiment, the target local control plane device obtains thecontext information of the UE in the following two manners:

Manner 1: The downlink data forwarding rule modification message sent bythe remote control plane device carries the context information of theUE, and the target local control plane device may obtain the contextinformation of the UE by parsing the downlink data forwarding rulemodification message.

Manner 2: The target local control plane device receives the contextinformation of the UE that is directly sent by the MME.

The context information of the UE includes a UE security context, abearer context, the TAI list, the GUTI, and index information of uplinkand downlink data forwarding rules. The local control plane devicestores this information.

S521. The target local control plane device sends the downlink dataforwarding rule modification message to the target gateway device.

It can be learned from the foregoing that in this embodiment of thepresent disclosure, due to a signaling proxy function of the localcontrol plane device, forwarding by the remote control plane device isnot required. A paging and service request process of a user may belocally implemented directly, and a signaling transmission path and timeare greatly shortened.

FIG. 6 is a schematic structural diagram of a local control plane deviceaccording to an embodiment of the present disclosure. The local controlplane device implements the control methods described in FIG. 1 to FIG.5A, FIG. 5B, and FIG. 5C. As shown in the figure, the local controlplane device in this embodiment of the present disclosure may include atleast an information obtaining module 510 and a bearer setup module 520.

The information obtaining module 510 is configured to obtain contextinformation of a user equipment from a remote control plane deviceaccording to an interaction process between the user equipment and theremote control plane device.

The context information of the user equipment includes at least asecurity context and a bearer context (including a user-plane addressand a user-plane TEID-U of an SGW, a TAI list, a GUTI, a control-planeTEID-C allocated by an MME, and a TEID-C allocated by the SGW). The TEIDis a tunnel endpoint identifier.

In one embodiment, the interaction process between the user equipmentand the remote control plane device includes an attach request processand a PDN connection setup process that are initiated by the userequipment.

In one aspect, as shown in FIG. 7, the information obtaining module 510may further include an information forwarding unit 511 and aninformation obtaining unit 512.

The information forwarding unit 511 is configured to: in the interactionprocess between the user equipment and the remote control plane device,forward, to a gateway device, forwarding plane modification informationsent by the remote control plane device, where the forwarding planemodification information carries the context information of the userequipment.

The information obtaining unit 512 is configured to obtain the contextinformation of the user equipment by parsing the forwarding planemodification information.

In another aspect, as shown in FIG. 8, the information obtaining module510 may further include an information forwarding unit 513 and aninformation receiving unit 514.

The information forwarding unit 513 is configured to: in the interactionprocess between the user equipment and the remote control plane device,forward, to the gateway device, forwarding plane modificationinformation sent by the remote control plane device.

The information receiving unit 514 is configured to receive the contextinformation of the user equipment sent by the remote control planedevice.

The bearer setup module 520 is configured to set up, by the localcontrol plane device according to the context information of the userequipment, a radio bearer between the user equipment and a base stationin which a current camping cell of the user equipment is located.

In one embodiment, after a service request sent by the user equipmentvia the base station in which the current camping cell of the userequipment is located is received, the bearer setup module 520 sends acontext setup request to the base station according to the contextinformation of the user equipment, so that the base station sets up theradio bearer between the base station and the user equipment.

Referring to FIG. 6, as shown in the figure, the local control planedevice in this embodiment of the present disclosure may further includea paging initiation module 530, configured to: after a downlink dataarrival notification message is received, initiate paging to the userequipment according to the context information of the user equipment, sothat the user equipment switches from an idle state to an active state,and sends the service request via the base station in which the currentcamping cell is located.

Referring to FIG. 6, as shown in the figure, the local control planedevice in this embodiment of the present disclosure may further includean information deletion module 540, configured to: after a contextdeletion request sent by the remote control plane device is received,delete the stored context information of the user equipment; and sendthe context deletion request to the gateway device, so that the gatewaydevice deletes the stored context information of the user equipment. Itshould be noted that the source gateway herein includes a source SGW butdoes not include a source PGW.

Referring to FIG. 6, as shown in the figure, the local control planedevice in this embodiment of the present disclosure may further includea notification sending module 550, configured to send a user statemodification notification to the remote control plane device, so thatthe remote control plane device modifies state information of the userequipment.

FIG. 7 is a schematic structural diagram of another local control planedevice according to an embodiment of the present disclosure. As shown inFIG. 7, the local control plane device may include: at least oneprocessor 601, such as a CPU; at least one network interface 603; amemory 604; and at least one communications bus 602. The communicationsbus 602 is configured to implement connection and communication betweenthese components. The network interface 603 may be a wireless interface,such as an antenna apparatus, and is configured to perform signaling ordata communication with another node device. The memory 604 may be ahigh-speed RAM memory, or may be a non-volatile memory, such as at leastone magnetic disk memory. In one embodiment, the memory 604 may furtherbe at least one storage apparatus located far away from the processor601. The memory 604 stores a group of program code, and the processor601 is configured to invoke the program code stored in the memory 604 toperform the following operations:

obtaining context information of a user equipment from a remote controlplane device according to an interaction process between the userequipment and the remote control plane device; and

setting up, according to the context information of the user equipment,a radio bearer between the user equipment and a base station in which acurrent camping cell of the user equipment is located.

In one embodiment, the interaction process between the user equipmentand the remote control plane device includes:

an attach request process and a packet data network connection setupprocess that are initiated by the user equipment.

In one embodiment, an operation in which the processor 601 obtains thecontext information of the user equipment from the remote control planedevice according to the interaction process between the user equipmentand the remote control plane device is:

in the interaction process between the user equipment and the remotecontrol plane device, forwarding to a gateway device, forwarding planemodification information sent by the remote control plane device, wherethe forwarding plane modification information carries the contextinformation of the user equipment; and

obtaining the context information of the user equipment by parsing theforwarding plane modification information.

In one embodiment, an operation in which the processor 601 obtains thecontext information of the user equipment from the remote control planedevice according to the interaction process between the user equipmentand the remote control plane device is:

in the interaction process between the user equipment and the remotecontrol plane device, forwarding to the gateway device, forwarding planemodification information sent by the remote control plane device; and

receiving the context information of the user equipment sent by theremote control plane device.

In one embodiment, an operation in which the processor 601 sets up,according to the context information of the user equipment, the radiobearer between the user equipment and the base station in which thecurrent camping cell of the user equipment is located is:

after receiving a service request sent by the user equipment via thebase station in which the current camping cell of the user equipment islocated, sending, according to the context information of the userequipment, a context setup request to the base station in which thecurrent camping cell of the user equipment is located, so that the basestation in which the current camping cell of the user equipment islocated sets up the radio bearer between the base station and the userequipment.

Correspondingly, before receiving the service request sent by the userequipment via the base station in which the current camping cell of theuser equipment is located, the processor 601 further performs thefollowing operation:

after receiving a downlink data arrival notification message, initiatingpaging to the user equipment according to the context information of theuser equipment, so that the user equipment switches from an idle stateto an active state, and sends the service request via the base stationin which the current camping cell is located.

Further, after obtaining the context information of the user equipmentfrom the remote control plane device according to the interactionprocess between the user equipment and the remote control plane device,the processor 601 further performs the following operations:

after receiving a context deletion request sent by the remote controlplane device, deleting the stored context information of the userequipment; and

sending the context deletion request to the gateway device, so that thegateway device deletes the stored context information of the userequipment.

In one embodiment, after setting up, according to the contextinformation of the user equipment, the radio bearer between the userequipment and the base station in which the current camping cell of theuser equipment is located, the processor 601 further performs thefollowing operation:

sending a user state modification notification to the remote controlplane device, so that the remote control plane device modifies stateinformation of the user equipment.

In one embodiment, the remote control plane device includes:

a mobility management entity of a conventional EPC network architecture;or

a central control plane device of a control-forwarding decouplingnetwork architecture.

In one embodiment, the context information of the user equipmentincludes:

a security context of the user equipment and a bearer context of theuser equipment, where the bearer context of the user equipment includesa user plane address, a tunnel identifier, a tracking area list, and aglobally unique temporary identity of a forwarding plane gateway, and acontrol plane identifier allocated by the remote control plane device.

An embodiment of the present disclosure further proposes a computerstorage medium. The computer storage medium stores a program, and theprogram includes several instructions that are used to perform some orall of operations in the control methods described in FIG. 1 to FIG. 5A,FIG. 5B, and FIG. 5C in the embodiments of the present disclosure.

In the embodiments of the present disclosure, the local control planedevice obtains the context information of the user equipment from theremote control plane device according to the interaction process betweenthe user equipment and the remote control plane device, and further setsup, according to the context information of the user equipment, theradio bearer between the user equipment and the base station in whichthe current camping cell of the user equipment is located. Therefore, asignaling transmission delay caused when the user equipment switchesfrom an idle state to an active state can be reduced, and a problem ofexcessive signaling interaction caused by a movement of the userequipment can be avoided.

A person of ordinary skill in the art may understand that all or some ofthe processes of the methods in the embodiments may be implemented by acomputer program instructing relevant hardware. The program may bestored in a computer readable storage medium. When the program runs, theprocesses of the methods in the embodiments are performed. The foregoingstorage medium may include: a magnetic disk, an optical disc, aread-only memory (ROM), or a random access memory (RAM).

What is disclosed above is merely example embodiments of the presentdisclosure, and certainly is not intended to limit the protection scopeof the present disclosure. Therefore, equivalent variations made inaccordance with the claims of the present disclosure shall fall withinthe scope of the present disclosure.

1. A control method comprising: obtaining, by a local control planedevice, context information of a user equipment from a remote controlplane device according to an interaction process between the userequipment and the remote control plane device; and setting up, by thelocal control plane device according to the context information of theuser equipment, a radio bearer between the user equipment and a basestation in which a current camping cell of the user equipment islocated, wherein the context information of the user equipment comprisesat least one of a security context of the user equipment or a bearercontext of the user equipment.
 2. The method according to claim 1,wherein the interaction process comprises at least one of: an attachrequest process initiated by the user equipment or a packet data networkconnection setup process initiated by the user equipment.
 3. The methodaccording to claim 1, wherein obtaining the context informationcomprises: in the interaction process between the user equipment and theremote control plane device, forwarding, by the local control planedevice, forwarding plane modification information from the remotecontrol plane device to the gateway device, wherein the forwarding planemodification information carries the context information of the userequipment; and obtaining, by the local control plane device, the contextinformation of the user equipment by parsing the forwarding planemodification information.
 4. The method according to claim 1, whereinobtaining the context information comprises: in the interaction processbetween the user equipment and the remote control plane device,receiving, by the local control plane device, the context information ofthe user equipment from the remote control plane device.
 5. The methodaccording to claim 1, wherein setting up the radio bearer comprises: inresponse to receiving a service request from the user equipment via thebase station, sending, by the local control plane device according tothe context information of the user equipment, a context setup requestto the base station.
 6. The method according to claim 5, wherein beforethe local control plane device receives the service request, the methodfurther comprises: in response to receiving a downlink data arrivalnotification message, initiating, by the local control plane device,paging to the user equipment according to the context information of theuser equipment.
 7. The method according to claim 1, wherein afterobtaining the context information, the method further comprises: inresponse to receiving a context deletion request from the remote controlplane device, deleting, by the local control plane device, the contextinformation of the user equipment; and sending, by the local controlplane device, the context deletion request to the gateway device.
 8. Themethod according to claim 1, wherein after setting up the radio bearer,the method further comprises: sending, by the local control planedevice, a user state modification notification to the remote controlplane device, wherein the user state modification notification is usedfor modification of state information of the user equipment.
 9. Themethod according to claim 1, wherein the remote control plane devicecomprises: a mobility management entity of an evolved packet core (EPC)network architecture; or a central control plane device of acontrol-forwarding decoupling network architecture.
 10. The methodaccording to claim 1, wherein the bearer context of the user equipmentcomprises at least one of a user plane address, a tunnel identifier, atracking area list, a globally unique temporary identity of a forwardingplane gateway, or a control plane identifier allocated by the remotecontrol plane device.
 11. A local control plane device comprising: atransceiver; and a processor configured to: obtain context informationof a user equipment from a remote control plane device according to aninteraction process between the user equipment and the remote controlplane device; and, set up, according to the context information of theuser equipment, a radio bearer between the user equipment and a basestation in which a current camping cell of the user equipment islocated, wherein the context information of the user equipment comprisesat least one of a security context of the user equipment or a bearercontext of the user equipment.
 12. The local control plane deviceaccording to claim 11, wherein the interaction process comprises atleast one of: an attach request process initiated by the user equipmentor a packet data network connection setup process initiated by the userequipment.
 13. The local control plane device according to claim 11,wherein the processor is configured to: in the interaction processbetween the user equipment and the remote control plane device, forwardforwarding plane modification information from the remote control planedevice to the gateway device, wherein the forwarding plane modificationinformation carries the context information of the user equipment; andobtain the context information of the user equipment by parsing theforwarding plane modification information.
 14. The local control planedevice according to claim 11, wherein the transceiver is configured toreceive the context information of the user equipment from the remotecontrol plane device.
 15. The local control plane device according toclaim 11, wherein the processor is configured to: after a servicerequest from the user equipment via the base station is received, sendaccording to the context information of the user equipment, a contextsetup request to the base station.
 16. The local control plane deviceaccording to claim 15, wherein the processor is further configured to:after a downlink data arrival notification message is received, initiatepaging to the user equipment according to the context information of theuser equipment.
 17. The local control plane device according to claim11, wherein the processor is further configured to: after a contextdeletion request from the remote control plane device is received,delete the context information of the user equipment; and send thecontext deletion request to the gateway device.
 18. The local controlplane device according to claim 11, wherein the transceiver is furtherconfigured to send a user state modification notification to the remotecontrol plane device, wherein the user state modification notificationis used for modification of state information of the user equipment. 19.The local control plane device according to claim 11, wherein the remotecontrol plane device comprises: a mobility management entity of anevolved packet core (EPC) network architecture; or a central controlplane device of a control-forwarding decoupling network architecture.20. The local control plane device according to claim 11, wherein thebearer context comprises at least one of a user plane address, a tunnelidentifier, a tracking area list, a globally unique temporary identityof a forwarding plane gateway, or a control plane identifier allocatedby the remote control plane device.